Process of making insulated conductors



2 Sheets-Sheet l lnvenor:

Aug. 9) v E. B. WHEELER PROCESS 0F MAKING INSULATED CONDUCTORS Filed Dec. l2, 1925 iL-J/ Edmund B. Wheeler by any.

Aug. 9, 1927. 1,638,556

E. B. WHEELER l PROCESS OF MAKING INSULATED CONDUCTORS Filed Dec. l2, 1925 2 Sheets-Sheet 2 /nvenfor'f I Edmund B. Wheeler Patented Aug. 9, 1927.`

EDNUND E. WHEELER, 'OE NEW YORK, N. Y.. AssIGNoR To WESTERN ELECTRIC COM- PANE, INCORPORATED, 'OE NEW YORK,N. Y., A CORPORATION OE NEW YORK.

PROCESS OF MAKING INSULATED COND'UACTORS.

Application led December 12, 1925. Serial No. 75,035.

cra-ck is materially reduced, if not entirely overcome, by embedding in the insulation threads substantially parallel to the core.

To attain this object a conductor having the desired characteristics is provided by a method which consists in bringing the core, pulp and threads into intimate relation in such a manner that the pulp is applied to lthe core and threads and caused to cling thereto with the threads embedded in the ulp. rlhis may be accomplished by sub- ]ectlng the core and threads to a liquid containing the pulp in such manner that pulp is a plied to the core and threads and` c aused to c ing thereto due to the surface tension of the liquid in Which the pulp is suspended and the felting action o the pulp. Where this method is used for coating a core in strand form, after the pulp is applied and attached to the core as just described, the pul and embedded threads may be formed whi e still moist to effect both a thorough intermingling of the pulp fibres and to cause the pulp to conform to the shape of the core. The embedded threads besides strengthening the insulation may be of selected colors to serve as means of identification of the insulated conductors when used in groups or l when coupled together. v

The invention will be more clearly understood from the following description tO- gether with the attached drawing forming a part thereof and in which:

Fig. 1 is a side elevation of a part of the paper pulp insulating machlne;

Fig. 2 1s an end view taken along line 2-2 of Fig. 1;

Fig. 3 is a view of the lower part of the drum considered as removed from the pulp tank and showing the arrangement of the metallic core or conductor and threads as .they pass around the drum;

ig. 4 is an enlarged detailed view inside elevation of the forming device;

Fig. 5 is an enlarged vertical sectional view of the forming device taken on line 5 5 of Fig.,4;

Fig. 6 is an enlarged fragmentary sectional view of the drum forconveying the core and threads into contact with the liquid containing pulp;

Fi 7 is an enlarged fragmentary sectiona view of the auxiliary roll for removing free liquid from the pulp deposited on the core;

Figs. 8, 9, 10 and 11 are enlarged views showing the form of the pulp coating on the core as it is delivered from the liquid containing pulp, the squeezing rolls and former, respectively.

The invention is illustrated in connection with the machine forming the subject of patent to H. G. Walker and A. T. March Patent No. 1,615,417 issued January 26, 1927.

`Reterring now to the drawin s in detail, in which like reference numera s designate similar parts throughout the several views,

the core to be coated is fed from a supply 20, over an idler roll 21, and thence around a drum 22 which is artly submerged in a liquid containing pu p within a semi-spherical ltrough 23. rlhe drum 22 comprises a pair of sheet metal sides 24, Fig. 6, and a peripheral portion 25 secured thereto. The

portion 25 is provided with a plurality of relatively large perforations 26 which are covered with a narrow strip of fine wire mesh 27. The core in passin around the drum lies upon the wire mesh 2 as is shown in Fig. 3. The drum 22 has a centrally disposed tubular axle 28 which is rotatably mounted in suitable bearings 29 carried by a framework 30 which supports all the elements of the apparatus. Su ported on a frame near the pulley 21 are our spools of thread 70. A ide plate 71 ha-ving four holes therein guides the threads 72 from the spools `70 so as to space them on the wire mesh 27 in relation to the core approximately as shown in Fig.y 3.

In order to applypulp to the core and threads as it passes over the drum 22 the pulp mixture within the drum is maintained4 at a lower level than that of the level of the pulp mixture in the tank 23, as indicated by dotted lines A and B respectively. This difference in levels is maintained by a siphon pipe 31 which has its inn l 'y e 1,638,556

of the liquid within the drum and the tank 23, the liquid in the tank 23 will pass through the wire mesh 27 and perforations 26, straining the pulp onto the outer surface of the wire mesh,.and applying pulp to the core and threads Supported thereon. order to keep the wire mesh clean prior to its reception of the core and a' new coatingv of pulp, it is washed by a jet of water under pressure which is supplied through a nozzle 33,

The drum 22 is rotated in the directionv indicated by the arrow. The core and threads with a coating of pulp thereon leaves the drum at the. top thereof, and the force of gravit surface tension of the liquid in the pu p mixture, and the felting action of the pulp fibers cause it to surround the core and threads and cling to itin substantially the form shown in Fig. 8.

From l the drum 22 the core and threads with a pulp coating .thereon is passed over an auxiliary roll 34 and then between a pair of squeezing rolls 35 and 36. These rolls are rotatably mounted between a pair of brack- 1 ets 37 secured to an upright standard 38 supported by the framework' 30. The shaft' carrying the roll 36 is driven through a pulley attached thereto which is actuated by a motor 39 in any suitable manner as by.

^ means of the belts 40 and 41 shown. lThe l 4 Wire mesh 42. It has been foun rolls 35 and 36 preferably draw the core from the supply roll 20, over the drum .22,`

causing it to rotate, and then between them. v The auxiliary roll 34, as shown in Fig. 7, is a hollow sheet metal drum having a peripheral slot covered with a stri of line preferable to employ the auxiliary roll 34 and to make it foraminous where it engages the core threads 'and pulp coating .thereon in order that the free liquid, so to speak, may be strained o away from the core and coating without causing a back flow of the liquid which would tend to wash oil' the pulp coating which at this stage is very soft and moist and easily removed from the core. With the free liquid removed the coating has greater strength due to a closer felting of the libers so that when the core and coating are passed through the squeezing rolls the coating will not be torn from the core.

The squeezing rolls may be formed of rubber and forced together by any suitable tension means which is adjustable to present the proper pressure on the core and pulp coating ,as they pass between the rolls. These rolls remove the greater portion of the liquidfrom the pulp mixture and form the pulp intoa thin ribbon which extends laterl ally from each side of the core as is shown in Fig. -9. y tends to mat or felt the fibers into more intimate relation1 increase'the tensile strength of the covering and secure it to the core.

From the squeezing rolls the core with its v ribbon pulp `coating is drawn through a This squeezing operation also former which wraps the projecting edges of the ribbon in which the threads are embeddedaround the core and around each other, the appearance of the coating after it is first actedv on by the former and after the forming action is completed being shown clearly in- Figs.` l0 and 11. The former causes a thorough intermingling of the pulp fibers and shapes the coating so that it embraces the core and conforms to the shape thereof and moulds `the coating into va mass so homogeneous that upon cutting thecore and coating the latter will not fra or ravel and will not become easily detache from the core.

The former, shown in detail in Figs. 4 and 5, comprises two cup shaped collars 43 and 44 held together and in'spaced relation by means-of rods 45. integral with said collars 43 and 44 areA sleeves 46 and *l 46' respectively which are rotatably mounted within suitable-bearings in the standards 37 and another pair 'of standards 47 supported by the framework 30. Two plates 48 and 49 have projecting tongues which are -bent around two of the rods 45 to pivotally support the plates in opposed relation to each other.

Compression springs 50 engage the rear faces of each of 'the plates 48 and 49 and tend to'force them together. The springs` 50 are put under the requisite compression by means of adjusting screws 51 which are mounted in brackets 52 'secured to ythe rods 45. The ends of the plates 49 and 48 adjacent the squeezing rolls 35 and 36 are dared outwardly so as to present a smooth surface to the core and pulp coating as they pass from the said rolls through the sleeve 46 and between the forming-plates 48 and 49. The core passes `:trom the forming plates through the sleeve 46. l' The plates 48 and 49 are rapidly rotated around the core and the pulp coating thereon through the medium of a pulley 18 secured to the sleeve 46 the pulley being driven by the motor 39 througha belt 17 The forming plates 48 and 49 wrap the projecting edgesfof the pulp ribbon about each other and around the core in much the same manner as though the core and pulp ribbon wererolled on a table top with the palm of the hand.

The core with its formed coatinoand embedded threads is drawn from the ormerand subjected to a mechanism (not shown) for thoroughly drying outI the coating.l This apparatus may be of any Well-known con-l struction, as shown for example in the said pending application.

It is understood that modifications may be made in the embodiment just described Without departing from the spirit and scope of the invention which should be limited only by the appended claims.

lVhat is claimed is: Y

1. A method of coatin a coreinv strand form having continuous brous threads adjacent thereto, consisting 'in subjecting the core and Afibrous threads to a liquid containing pulp, in such a manner that pulp is applied thereto, and then forming the pulp on the core and threads to constitute a coating conforming with the core and retained on the core by a felting ofthe pulp fibers. j

2. A method of coating a core in strand form having continuous fibrous threads adjacent thereto, consisting in applying pulp to the core and fibrous threads to cause it to be attached thereto in ribbon form and wrapping the ribbon and embedded threads around the core to constitute a reinforced.

manner that pulp is deposited) thereon squeezing the core, the deposited ulp and embedded threads so that the p forms a ribbon and then wrappin sai ribbon and embedded threads aroun the core and around itself to form a tube of felted fibers reinforced by said threads surrounding the core.

In witness whereof, I hereunto subscribe my namel this 8th day of December, A. D.

EDMUND B. WHEELER.

in such' 

